Re: [PATCH -next] hrtimer: Fix hang seen if tick_init_highres() failed
From: Luiz Capitulino
Date: Sat Aug 22 2015 - 17:26:20 EST
On Sat, 22 Aug 2015 01:10:47 -0700
Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> Commit 75e3b37d0598 ("hrtimer: Drop return code of hrtimer_switch_to_hres()")
> drops the return code of hrtimer_switch_to_hres(). While doing so, it also
> drops the return statement itself on failure. This may cause a system hang.
> Seen when running arm:multi_v7_defconfig in qemu with devicetree file
> vexpress-v2p-ca9.
>
> Fixes: 75e3b37d0598 ("hrtimer: Drop return code of hrtimer_switch_to_hres()")
> Cc: Luiz Capitulino <lcapitulino@xxxxxxxxxx>
> Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Thanks for catching it Guenter!
Reviewed-by: Luiz Capitulino <lcapitulino@xxxxxxxxxx>
> ---
> kernel/time/hrtimer.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
> index 5c4fe50e47d3..457a373e2181 100644
> --- a/kernel/time/hrtimer.c
> +++ b/kernel/time/hrtimer.c
> @@ -695,6 +695,7 @@ static void hrtimer_switch_to_hres(void)
> if (tick_init_highres()) {
> printk(KERN_WARNING "Could not switch to high resolution "
> "mode on CPU %d\n", base->cpu);
> + return;
> }
> base->hres_active = 1;
> hrtimer_resolution = HIGH_RES_NSEC;
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/